The semiconductor integrated circuit (IC) industry has experienced rapid growth. Continuing advances in semiconductor manufacturing processes have resulted in semiconductor devices with finer features and/or higher degrees of integration. Functional density (i.e., the number of interconnected devices per chip area) has generally increased while feature size (i.e., the smallest component that can be created using a fabrication process) has decreased. This scaling-down process generally provides benefits by increasing production efficiency and lowering associated costs.
In the semiconductor IC industry, manufacturers are currently imbedding dynamic random access memory (DRAM) arrays on the same substrate as CPU cores or other logic devices. This technology is being referred to as embedded DRAM (EDRAM). Embedded DRAM generally can provide micro controller (MCU) and other embedded controllers faster access to larger capacities of on-chip memory at a lower cost.
A semiconductor memory, such as a DRAM or embedded DRAM, mainly consists of a transistor and a capacitor. However, as the feature sizes shrink further and density requirements increase, it is getting more difficult to form the capacitor. It is desirable to have an improved fabrication process for forming an EDRAM device.